GL-X750 power connector

Replying to another thread about the X750 reminded me of a question I’ve been meaning to post. I could do with buying a replacement power adaptor for home (with a longer cable than the short one bundled with the router) so I can mount it in a more convenient place.

What is the correct size of the ‘barrel’ power connector on the GL-X750 power supply? It looks like a 3.50mm/1.35mm outside/inside diameter one, but there are lots of very close variants available, e.g. 3.5/1.4, 3.5/1.3, 3.5/1.25, etc. Even having the plug in my hand, I can’t measure the inside diameter with that kind of accuracy! :see_no_evil:

What is the correct size of the ‘barrel’ power connector on the GL-X750 power supply?

  • outside/inside 4.0/1.7
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Thanks, that’s wider outside diameter than I thought; it was definitely worth asking!

Is there any special reason a “normal” sized 12V barrel jack couldn’t be used? Almost every other 12V device I have uses a common jack and I can share power supplies as long as they have the appropriate amperage rating. The Spitz is my one “special” device that needs its own cable, very inconvenient at times.

Be careful or you will blow your devices up - amperage rating is not important - voltage is the thing that needs to match.

We’ve already established we’re dealing with 12V power here, but thanks for playing.

Reality: any amperage over what the device requires is fine, and most “12V” devices will accept a voltage range between 9-18V. This is not a universal rule, I certainly wouldn’t do it unless I knew it could handle it, but a sufficiently robust buck-boost regulator won’t care. Maybe read (and quote) my entire post next time before posting your hot-take.

It wasn’t obvious to me and I hope I helped save other readers devices by making it clearer.
Sorry that you are on the sensitive side and took it as an insult!

You know you almost fooled me, I was almost ready to apologize for mischaracterizing your initial post before I reread your reply, but you just couldn’t resist that last jab, eh? It’s pretty clear what your intention was, and I’m sure it wasn’t to help anyone. So again, thanks for playing but you won’t get an easy capitulation from me, I don’t suffer low-effort trolls.

A quick postscript in case anyone finds it useful: the Amazon Echo Dot is a 12V device with a 4.0/1.7mm barrel connector, the correct polarity and similar current demand, so the mass-market replacement adaptors available for that also work nicely with the X750.

@ChrisW Thanks for the hint with the Amazon Echo Dot adapter compatibility :v: That opened new results on local market searches! Let’s see if the car charger with 12V DC stabilizer and the USB adapter with 5V DC to 12V DC work …

So will this product work for DC power supply?

Looks good, but…

USB Input: 5V A male; DC Output: 12.0V; Max current: 0.6A; 

Look at the bottom of the Router to see what current it pulls (12V @ 1.5A for GL-X750V2). I wouldn’t like to guarantee connection stability.

Would this product work?

Thanks for your response - think I found a better one accordingly -

It says it will…

USB Input: 5V A male; DC Output: 12V; Max current: 2A;

I do have reservations though. Are you feeding this from a ‘Wall Wart’, or a computer USB because
12V x 2A = 24W
24W / 5V = 4.8A
So whatever you use needs to be able to supply 5A@5V to be up to the job without blowing something. Computer ports usually supply nowhere near this current. See my comments here.

My advice would be to get a >3A 12V DC Wall Wart and use that to supply the Router. Damage to your computer due to drawing too much current through the USB could be a problem as they are usually specced quite low and are meant for periherals.

Thank you for your answer. I am feeding this by a DC battery bank on a boat and not a computer. Will that make it so that this works?

As long as it can supply 12V@2A, but why are you dropping to 5V? Current will be limited to whatever that 5V Power Supply is rated to. Why not drop to 12V instead of 5V and just use that?

The other thread with the DC to DC convertor (Buck/Boost) will do what you need and is able to supply 12V@3A, but now we are getting some detail, all be it drip fed! What voltage is available from the ‘DC Battery Bank’? Is it less than 28V?

Tell us what you have. A Battery Bank in a boat? Or a Battery Bank used to supply 5V USB outputs?? What Voltage? How many Ampere hours? How are the batteries charged? The Buck/Boost PSU will keep the output constant to protect the Router. If it is supplied at a voltage greater than 12V constantly, you can get away with a Buck Convertor, but then the Buck/Boost will give some insurance should the batteries drain too far…

Once we know EXACTLY what you have then there is a chance we can help. Instead of us having to guess, you need to provide details to help us to help you…

I appreciate your help here - I am not good at electronics stuff so forgive my drip feeding. The boat is a 12v system, and has AGM batteries that have about 700ah. My challenge here has always been - how do I supply the right amount of power to the router since the plug that came with the unit is for an AC system. I am new to all this stuff - would a buck converter be hard wired to the boat’s 12v system and hardwired into the router as well? I was hoping for something that was plug and play but that isn’t happening - I just need to know how to get the router connected to my boat’s battery since the router did not come with a cigarette lighter or USB plug in. Trying here, but I am a newbie and I appreciate your help.

Excellent, we now have something to work with.

Personally, I would fit a fused DC/DC Buck/Boost regulator to ensure that there is a regulated 12V DC supply available. This will protect the Router. For Example..

Then I would fit something like this which will give USB outputs as well.

Then a lead like this

So, a fused 12V Buck/Boost Power Supply into a fused Panel Cigarette/USB outlet and the a 12V Cigarette Plug with the 4.0/1.7 lead to the router. You are dealing with electronics, so the fuses are essential.

Now the disclaimer, I have not tried any of these and you use them at your own risk! I do have a similar setup in my RV/Motorhome, but it is all .Homebrew’ kit.


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Thank you very much for your assistance!

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